1. Field of the Invention
The invention relates to a guide device for the movable roof element of an openable vehicle roof with a guide sliding block connected to the roof element and with a guide unit which has two guide surfaces which route the guide sliding block between themselves and which face in opposite directions, one of the guide surfaces being held on the guide unit to be able to move relative to the guide sliding block and being pretensioned relative to the other guide surface by a spring means.
2. Description of Related Art
With a guide device of the type indicated above, the roof element can be raised and lowered again by relative lengthwise movement of the guide unit along the guide sliding block.
German Patent DE 101 44 756 C2 and corresponding U.S. Pat. No. 6,890,025 B2 discloses a generic guide device in which a slide element of a guide unit or guide claw is pressed against a sliding block path with spring-elastic pretensioning and an opposite surface of the guide claw adjoins the opposite side of the sliding block path. The spring-elastic pretensioning is provided by a single elastomeric spring element which is surrounded by the bush-shaped slide element. With consideration of the existing installation space, the support surface of this spring element is too small for the cover of an openable vehicle roof which has a large mass and which is to be guided by the guide device in order to be able to prevent rattling of the guide device over an uneven roadway surface with sufficient elasticity of support.
European Patent EP 1 070 614 A1 and corresponding to U.S. Pat. No. 6,325,453 B1 discloses a guide device in which the guide claw has a guide recess in which a guide bridge is movably held. In the guide claw, there is an elastic element in the form of a spring which forms the lower guide surface for the guide bridge and it has convex section which presses against the guide bridge so that play between the guide claw and the guide bridge is compensated. The spring is in sliding contact with the guide bridge. In order to be able to carry out its support function, it must press with distinct force against the guide bridge, by which friction is increased. The elastic behavior of such a spring is inadequate.